The Carbon Emission Reduction Target (CERT) placed a five year obligation on gas and electricity suppliers to reduce carbon emissions in the household sector through energy efficiency improvements. It ran from April 2008 – December 2012.
Overall CERT resulted in almost 4 million households receiving professionally-installed loft insulation; 2.6 million households receiving professionally-installed cavity wall insulation and an estimated 2.8 million additional households receiving ‘DIY’ loft insulation materials.
Early criticisms of the scheme included the large number of energy saving light bulbs supplied to households without the necessary monitoring of their installation or of savings achieved. This was addressed by removing such items from the scheme and obliging suppliers to provide much of the savings through insulation measures.
The green deal has now replaced CERT.